1. Field of the Invention
This invention relates to a high-frequency loudspeaker, meaning a loudspeaker for sound in the high-frequency range, this having a movable diaphragm and an actuating unit connected to this diaphragm which unit, under the action of an electrical signal to be converted into sound waves, is variable in dimensions along at least two opposite directions. High-frequency loudspeakers of this kind are called "tweeters".
2. Prior Art
In loudspeakers of the kind set forth the diaphragm is usually in the form of a hemisphere and is then called a spherical loudspeaker. There are however high-frequency loudspeakers with other forms of diaphragm, for example funnel-shaped. All these loudspeakers however send out sound in a selected direction. As a consequence, to obtain a good stereophonic or quadrophonic effect it is necessary for these known loudspeakers to be orientated in such a way that the sound waves they send out converge at one point or one listening area. The hearer must be located in this convergence area and this means firstly disadvantages as regards the spacial arrangement of the loudspeaker and secondly a limitation of the number of hearers who will all wish to be located in the preferred listening area. Further it is usual to house these known high-frequency loudspeakers in special housings, frequently in box-type cabinets. Arrangements of this nature increase the expense for sound systems and take up a lot of room.